Hong Kong is shortening the quarantine period to seven days for vaccinated travellers arriving in the city who show sufficient antibodies. The new measures are only applicable to people who have logged 14 days following their second vaccination dose. At a press briefing, Hong Kong Chief Executive Carrie Lam said the change will take effect from the end of the month. But for those arriving from countries deemed "very high risk," the quarantine period remains 21 days.